Therapy and diagnosis system and method with distributor for distribution of radiation

ABSTRACT

A distributor for a system for interactive interstitial photodynamic and photothermal tumor therapy and tumor diagnosis, comprises a plurality of primary radiation conductors arranged for conducting radiation to and from the tumor site, a plurality of secondary radiation conductors, two flat discs abutting against each other, wherein a first of said discs is fixed and the second of said discs is turnable relatively to the other disc, and each disc has holes arranged on a circular line. The proximal ends of the primary radiation conductors are fixed in the holes of the fixed disc and distal ends of the secondary radiation conductors are fixed in the holes of the turnable disc, whereby the primary and the secondary radiation conductors by rotation of the turnable disc are connectable to each other in different constellations.

BACKGROUND OF THE INVENTION

The invention relates to a system and a method for interstitialphotodynamic and photothermal tumor therapy and diagnosis of a tumor ata tumor site in a body, wherein radiation is conducted to the site forsaid therapy and diagnosis. The system comprises a distributor ofradiation from at least one therapeutic radiation source and adiagnostic radiation source to said tumor, and from the tumor to atleast one radiation sensor, respectively.

Within the field of medical therapy of tumor diseases, a plurality oftreatment modalities has been developed for the treatment of malignanttumor diseases, e.g. a tumefaction. Operation, cytostatics treatment,treatment with ionising radiation (gamma or particle radiation), isotopetherapy, and brachy therapy employing radioactive needles are examplesof common treatment modalities. In spite of great progress withintherapy, the tumor diseases continue to account for much humansuffering, and are responsible for a high percentage of deaths inWestern countries. A relatively new treatment modality, photodynamictherapy, commonly abbreviated PDT, provides an interesting complement oralternative in the treatment field. A tumorseeking agent, normallyreferred to as a sensitizer, is administered to the body intravenously,orally or topically. It accumulates in malignant tumors to a higherextent than in the surrounding healthy tissue. The tumor area is thenirradiated with nonthermal red light, normally from a laser, leading toexcitation of the sensitizer to a more energetic state. Through energytransfer from the activated sensitizer to the oxygen molecules of thetissue, the oxygen is transferred from its normal triplet state to theexcited singlet state. Singlet oxygen is known to be particularly toxicto tissue; cells are eradicated and the tissue goes in necrosis. Becauseof the localization of the sensitizer to tumor cells a uniqueselectivity is obtained, where surrounding healthy tissue is spared. Theinitial clinical experience, using in particular haematoporphyrinderivative (HPD) and delta amino levulinic acid (ALA) are good.

Sensitizers also exhibit a further useful property; to yield acharacteristic red fluorescence signal when the substance is excitedwith violet or ultraviolet radiation. This signal clearly appears incontrast to the autofluorescence of the tissue and can be used tolocalize tumors and for quantifying the size of the uptake of thesensitizer in the tissue.

The limited penetration in the tissue of the activating red radiation isa big drawback of PDT. The result is that only tumors up to about 5 mmthickness can be treated by surface irradiation. In order to treatthicker and deep-lying tumors, interstitial PDT (IPDT) can be utilized.Here, light-conducting optical fibers are brought into the tumor using,e.g. a syringe needle, in the lumen of which a fiber has been placed.

In order to achieve an efficient treatment, several fibers have beenused to ascertain that all tumor cells are subjected to a sufficientdose of light so that the toxic singlet state is obtained. It has beenshown to be achievable to perform dose calculations of the absorptiveand scattering properties of the tissue. E.g., in the Swedish patent SE503 408 an IPDT system is described, where six fibers are used fortreatment as well as for measurement of the light flux which reaches agiven fiber in the penetration through the tissue from the other fibers.In this way an improved calculation of the correct light dose can beachieved for all parts of the tumor.

In the equipment described in SE 503 408 the light from a single laseris divided up in six different parts using a beamsplitter systemcomprising a large number of components. The light is then focused intoeach of the six individual treatment fibers. One fiber is used as atransmitter while the other fibers are used as receivers of radiationpenetrating the tissue. For light measurement light detectors are swunginto the beam path which thus is blocked, and the weak light, whichoriginates from the fibers that collected the light which isadministered to the tissue, is measured.

However, such open beam paths result in a strongly lossy beamsplittingand the resulting losses of light drastically impair the lightdistribution as well as the light measurement. Furthermore, such asystem must often be adjusted optically, which is also an importantconsideration in connection with clinical treatments.

SUMMARY OF THE INVENTION

In one embodiment, the invention comprises a system for interactiveinterstitial photodynamic or photothermal tumor therapy and tumordiagnosis, comprising at least one therapeutic radiation source and atleast one diagnostic radiation source, at least one diagnostic radiationsensor, and at least two primary radiation conductors which at theirdistal ends are interstitially arranged in a tumor site, wherein theprimary radiation conductors in use are employed as a transmitter fordiagnostic radiation from said diagnostic radiation source for diagnosisof a tumor at said tumor site, or for therapeutic radiation from saidtherapeutic radiation source for therapy of the tumor, respectively oras a receiver for conduction of radiation from the tumor site fordiagnosis of the tumor at the tumor site, and a distributor fordistribution of radiation from the diagnostic and therapeutic radiationsource to the tumor site, and from the tumor site to at least onediagnostic radiation sensor. In preferred embodiments, the distributorcomprises a plurality of primary radiation conductors arranged forconducting radiation to and from the tumor site, a plurality ofsecondary radiation conductors arranged for delivering radiation fromthe diagnostic or therapeutic radiation source or conduction ofradiation to the diagnostic radiation sensor, two flat discs abuttingagainst each other, wherein a first of said discs is fixed and thesecond of said discs is turnable relatively to the other disc, andwherein each disc has holes arranged on a circular line. The proximalends of the primary radiation conductors are fixed in the holes of thefirst disc and distal ends of the secondary radiation conductors arefixed in the holes of the second disc, whereby the primary and thesecondary radiation conductors by rotation of the two discs relativeanother are connectable to each other in different constellations.

In another embodiment, a method for interactive interstitialphotodynamic or photothermal tumor therapy and diagnosis. The methodpreferably comprises inserting at least two primary radiation conductorsat distal ends thereof interstitially into a tumor, activating adiagnostic radiation source and transmitting diagnostic radiationthrough one of said primary radiation conductors to the distal endsthereof, transmitting the diagnostic radiation through tissue at saidtumor site to distal ends of the remaining primary radiation conductors,collecting and evaluating diagnostic information from radiation receivedfrom said tumor, automatically switching between tumor therapy and tumordiagnostics, and controlling the tumor therapy by regulating atherapeutical radiation intensity depending on said diagnosticinformation.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more closely explain the invention a number of embodimentsof the invention will be described in the following with reference tothe figures, wherein

FIG. 1 is a schematic perspective view of a first embodiment of thesystem according to the invention, wherein light conductors arranged insaid invention are interstitially inserted in a tumor,

FIG. 2 is a view similar to FIG. 1, where the discs of the distributorare brought apart,

FIG. 3 is a planar view from above of the turnable distributor disc withholes arranged in said disc,

FIG. 4 is a fragmentary cross section view of the turnable disc of saiddistributor, wherein a springloaded ball is provided,

FIG. 5 is a schematic perspective view illustrating the use of thesystem according to the invention with the distributor in the mode oftumor diagnostics,

FIG. 6 is a view similar to FIG. 5 and FIG. 2, where two distributorsare arranged on the same single axis, and

FIG. 7 is a schematic perspective view illustrating the use of thesystem according to the invention, with the distributor in the mode ofphotodynamic treatment of a tumor.

DETAILED DESCRIPTION OF THE INVENTION

A preferred embodiment of the distributor of the system according to theinvention is now described with reference to FIG. 14. The distributor 1comprises two flat and in proximity lying discs made of, e.g. 1 cm thicksteel. The discs are hereby arranged on an axis 2, wherein one of thediscs is a fixed disc 3 and the other one is a turnable disc 4. Thediscs 3 and 4 are abutting against each other in FIG. 1 and separatedfrom each other in FIG. 2.

Evenly distributed holes 5 lying on a circle are arranged in both discs(FIG. 3) for fixation of primary radiation conductors 6 in one of thediscs and secondary radiation conductors 7 in the other disc,respectively. Preferably the diameter of the holes is 0.3–0.7 mm. Inorder to attain a high precision, allowing the light conductors to bearranged exactly face to face, the holes of the two discs can be drilledtogether, maybe with a centering tube. Then the common axis 2 isutilized. It is thus possible to achieve a very high precision whenmaking the series of holes.

By employing discs drilled together, radiation conductors can be fixedin said discs, wherein an extra, thinner disc then can be turnedslightly, preferably springloaded, so that all light conductors aresimultaneously pinched in their positions without the need for any glueor other fixation means. Alternatively, the diameter of the holes ismade larger than the diameter of the light conductors, wherein the holescan be dressed with an appropriate piece of tubing, or the ends of thelight conductors can be supplied with a fitted hose. Alternatively, theends of the light conductors can be flared or flanged into the holes.

Preferably the light conductors are optical fibers, wherein differenttypes of hoses or flexible tubes containing a light-conducting materialare included. The light conductors should have such a length and bearranged in such a way that the turnable disc 4 can be turned withoutproblems a full turn (360 degrees). The direction of movement can bereversed to avoid the light conductors forming a spiral.

According to the invention a plurality of primary light conductors 6 ina system are arranged in the fixed disc 3 for conduction of radiation toand from a reaction site 8. By a reaction site we in the present contextmean a site where photodynamically active compounds will react in atumor when subject to therapy. E.g., by being forwarded through thelumen of injection needles which are placed in the tumor, these primaryradiation conductors 6 are then fixed in the reaction site 8. Then theprimary radiation conductors are moved forward to arrive outside thedistal end of the needle. The same light conductor 6 is used all thetime for integrated diagnostics and dosimetry, to avoid that the patientbe subjected to multiple pricks.

The holes 5 in the fixed disc 3 as well as in the turnable disc 4 arearranged on a circular line, wherein the circle radius on one discequals the circle radius on the other disc. The holes on one disc areequally distributed along the circle line with an angular separation of

v₁=(360/n₁) degrees, where n₁ equals the number of holes, and the holesof the other disc are equally distributed along the circle line with anangular separation v₂ equalling (360/n₂) degrees. The proximal ends ofthe primary radiation conductors 6 are fixed in the holes of the fixeddisc 3, and distal ends of the secondary radiation conductors 7 arefixed in the holes of the turnable disc 4. In order to make the holes,and thereby the primary and secondary radiation conductors in both discsconnectable to each other in different constellations by turning of theturnable disc 4, n₂ is selected to be a multiple of n₁, in such a waythat n₂ is obtained as an integer larger or equal to 1. Suitably thenumber of holes in the fixed disc is chosen from two to more than six.

Preferably six holes are arranged in the fixed disc 3 and twelve holesare arranged in the turnable disc 4. With six primary radiationconductors 6 the angular separation will accordingly become 60 degreesin the fixed disc 3 and with twelve holes arranged in the turnable disc4 the angular separation will become 30 degrees for the secondaryradiation conductors 7.

In order to facilitate the comprehension of the invention the followingdescription of a preferred embodiment of the distributor of the systemaccording to the invention relates to six primary radiation conductors 6arranged with their proximal ends in the fixed disc 3 for conduction ofradiation to and from the reaction site 8 at the distal ends of theprimary radiation conductors.

Thus, the turnable disc 4, as well as the fixed disc 3, have six holes 5for corresponding six diagnostic secondary radiation conductors 7, and,in addition, six further holes for six therapeutic secondary radiationconductors 7. All these twelve radiation conductors 7 can releaseradiation to the reaction site 8 and receive radiation from said site.Thus, several spectra can be recorded and read out simultaneously.

By turning the turnable disc 4 the primary and the secondary radiationconductors become connectable to each other in different constellations.An exact positioning of the opposing radiation conductors in thedistributor 1 is facilitated by arranging means for stopping theturnable disc 4 in predetermined angular positions. E.g., groves 10 canbe arranged in the axis 2 for catching a springloaded ball 11 arrangedin the turnable disc 4 (FIG. 4).

In order to allow a fast and efficient switching between a diagnosticmode and a therapeutic mode, every other of the secondary lightconductors of the distributor 1 according to the invention, are dividedinto a diagnostics and into a therapeutic series. Both series of holesare arranged on the same circle, but displaced by 30 degrees with regardto each other. A specific therapeutic light conductor 7 a′ in thediagnostic series of every other secondary light conductor is arrangedfor emitting radiation from at least one diagnostic radiation source 9a. The other, non specific diagnostic radiation conductors 7 a in thediagnostic series of secondary radiation conductors are arranged forconduction of radiation to at least one diagnostic radiation sensor 12.The therapeutic series of every other secondary radiation conductor 7 bis for therapeutical purposes arranged to emit radiation to the reactionsite 8 from at least one therapeutic radiation source 9 b.

In the preferred embodiment of the invention, the primary and secondaryradiation conductors are optical fibers, which in the distributor 1shown in FIGS. 1 and 2 are connected to the fixed disc 3 as well as theturnable disc 4. Out of the fibers, which are connected to the turnabledisc 4, six diagnostic fibers can be used for diagnostic purposes andsix therapeutic fibers can be used of therapeutical purposes. However,in the diagnostic mode, from one to more than three modalities can beemployed.

With reference to FIGS. 5–7 only the presently described radiationconductors which are coupled to a turnable disc are for clarifyingpurposes shown; the other radiation conductors are not shown althoughthey are coupled to said disc.

By turning the turnable disc 4 by 30 degrees the primary fibers 6 whichat their distal ends, respectively, are optically coupled to the tissueof the patient can be employed for therapy as well as diagnostics andmeasurements. One out of every diagnostic secondary radiation conductor7 is in the diagnostic mode connected to different radiation sources fordiagnostics, while the other five diagnostic radiation conductorsreceive signals, which are related to the interaction of thesediagnostic radiation sources with the tissue.

Since intensity as well as spectral resolution is of interest, thedistal ends of these five diagnostic radiation conductors are arrangedin a slit-like arrangement so that they overlap the entrance slit and/orconstitute the entrance slit of the radiation sensor 12, which is acompact spectrometer and is supplied with a two-dimensional detectorarray. The recording range of the spectrometer is preferably within therange 400 to 900 nm. Each of the diagnostic radiation conductors 7 a canof course be connected to an individual radiation detector 12 in theform of a spectrometer or another type of detector, e.g. a compactintegrated spectrometer.

With reference to FIG. 5 the specific diagnostic radiation conductor 7a′ is connected to an arrangement similar to the distributor 1, whichcomprises a second fixed disc 13 and a second turnable disc 14 which arearranged on a common axis 15. All fixed and turnable discs can also bearranged on one single axis as is shown in FIG. 6. A more compact androbust construction is obtained in this way.

More specifically the diagnostic radiation conductor 7 a′ is proximallyarranged in a single hole on the second fixed disc 13. Furtherdiagnostic light conductors 17 are arranged on a circle in said secondturnable disc 14; in this case three diagnostic light conductors whichat their proximal end, respectively, are connected to differentradiation sources 9 a, and which each are connectable to the diagnosticradiation conductor 7 a′ and further on to a primary radiation conductor6′ comprised in the different primary radiation conductors 6 (See FIG.5).

Preferably the diagnostic radiation source 9 a is a laser of the samewavelength as the one utilized for the laser irradiation forphotodynamic tumor therapy, but of substantially lower output power.Suitable filters can be arranged on the second turnable disc 14, to beturned into the light path of the diagnostic radiation sensor 12 inorder to secure that the correct dynamic range is utilized for allmeasurement tasks.

Certain of the diagnostic radiation sources 9 a are utilized in order tostudy how radiation (light) of the corresponding wavelength ispenetrating through the tissue of the tumor. When light from adiagnostic radiation source 9 a is transmitted through the particulardiagnostic radiation conductors 17, 7 a′, 6′ via the discs 14, 13, 4, 3,respectively, into the tissue 8, one of the primary radiation conductors6, which is the radiation conductor 6′ opposing the diagnostic radiationconductor 7 a′ in the distributor 1, will function as a transmitter intothe tumor 8, and the other five primary radiation conductors 6 havingtheir distal ends arranged in the tumor 8 will act as receivers andcollect the diffuse flux of light reaching them. The light collected isagain conducted via the discs 3, 4, and diagnostic radiation conductors7 a to the radiation sensor 12 and five different light intensities canbe recorded on the detector array.

When the turnable disc 4 is turned by 60 degrees, the next primaryradiation conductor 6 to the patient will get the role as transmitter,and the five others become the receivers for a new light distribution.After four further turns of the turnable disc 4, each by 60 degrees tothe following primary radiation conductor 6 in the patient, light fluxdata for all remaining combinations of transmitters/receivers have beenrecorded. Thus, in total 6*5=30 measurement values are obtained and canbe used as input data for a tomographic modelling of the optical dosebuild up in the different parts of the tumor during the course of thetreatment.

As an alternative to a specific wavelength, radiation from a white lightsource can be coupled into the particular diagnostic light conductor 7a′ and into the tissue from the distal end of primary radiationconductor 6′. From the distal end of primary radiation conductor 6′, onpassage through the tissue to the distal end of the receiving lightconductor 6 in the patient, the well-defined spectral distribution ofthe diagnostic radiation source 9 a will be modified by the tissueabsorption. Then, oxygenated blood yields a different signature thannon-oxygenated blood, allowing a tomographic determination of the oxygendistribution utilizing the thirty different spectral distributions whichare read out, five spectra at a time in the six possible differentconstellations on rotation of the turnable disc 4 during a diagnosticinvestigation. Such a determination of the oxygenation in the tumor isimportant, since the PDT process requires access to oxygen in thetissue.

Finally, a light source for blue/violet or ultraviolet light, e.g. alaser, can be coupled to the particular radiation conductor 7 a′. Thenfluorescence is induced in the tissue, and a sensitizer administered tothe tissue displays a characteristic red fluorescence distribution inthe red/near-infrared spectral region. The strength of the correspondingsignal allows a quantification of the concentration of the sensitizer inthe tissue.

Since the short wavelength light has a very low penetration into thetissue, the induced fluorescence must be measured locally at the tip ofthe distal end of the primary radiation conductor. For this task thereis in this case for the corresponding radiation source 9 a at theproximal end of the particular diagnostic radiation conductor 17 abeamsplitter 18, which is preferably dichroitic, transmitting theexciting light but reflecting the red-shifted fluorescence light. Thisreflected light is focused into the proximal end of a conveyingradiation conductor 19, the distal end of which is connected to theradiation sensor 12, which records the fluorescence light distribution.A suitable self-contained fluorosensor is described in Rev. Sci. Instr.71, 3004 (2000).

By rotating the turnable disc 4, the fluorescence which is proportionalto the concentration of the sensitizer, can be measured sequentially atthe tips at the distal ends of the six primary radiation conductors.Since the sensitizer is bleached by the strong red treatment light,being particularly strong just around the tip of the primary radiationconductor 6′, it is essential to make this measurement before the startof the treatment.

If the tips of the primary radiation conductors 6 in addition aretreated with a material, the fluorescence properties of which aretemperature dependent, sharp fluorescence lines are obtained uponexcitation, and the intensity of the lines and their relative strengthdepend on the temperature of the tip of the radiation conductor 6′.Examples of such materials are salts of the transition metals or therare earth metals. Thus also the temperature can be measured at the sixpositions of the six radiation conductors, one at a time. The measuredtemperatures can be utilized to find out if blood coagulation with anassociated light attenuation has occurred at the tip of the radiationconductor 6 and for studies regarding the utilization of possiblesynergy effects between PDT and thermal interaction. Since the linesobtained are sharp, they can be lifted off the more broad-bandedfluorescence distribution from the tissue.

The concentration of the sensitizer can for certain substances bemeasured in an alternative way. Then the red light used for the lightpropagation studies is used to induce near-infrared fluorescence. Thisfluorescence penetrates through the tissue to the tips of the receivingprimary radiation conductors 6, and are displayed simultaneously asspectra obtained in the radiation sensor 12. A tomographic calculationof the concentration distribution can be performed based on in totalthirty measurement values.

After diagnostic measurements and calculations have been performed, theprimary fibers 6 optically coupled to the tissue of the patients can beutilized for therapy by rotation of the turnable disc 4 by 30 degrees.Referring to FIG. 7, the therapeutic radiation conductors 7 b of everyother secondary radiation conductor 7 is utilized, now connected to theopposing radiation conductors 6 via the distributor 1. Each or the sixtherapeutic radiation conductors 7 b is connected to an individualtherapeutic radiation source 9 b, which preferably is a laser sourcewith a wavelength which is adapted to the absorption band of thesensitizer. At the photodynamic tumor treatment a dye laser or a diodelaser is preferably used, with a wavelength which is selected withregard to the sensitizer employed. For Photofrin® the wavelength is 630nm, for δ amino levulinic acid (ALA) it is 635 and for phthalocyaninesit is around 670 nm. The individual lasers are regulated during thetreatment to a desirable individual output power. If desired, they mayhave built-in monitoring detectors.

The therapeutical treatment can be interrupted and new diagnostic datacan be processed in an interactive method till an optimal treatment hasbeen reached. This method can include synergy between PDT andhyperthermia, where an increased temperature is reached at increasedfluxes of laser radiation. The whole process is controlled using acomputer, which does not only perform all the calculations but also isutilized for regulation.

1. A system for interactive interstitial photodynamic or photothermaltumor therapy and diagnosis, said system comprising: at least onetherapeutic radiation source and at least one diagnostic radiationsource; at least one diagnostic radiation sensor, and at least twoprimary radiation conductors which at their distal ends areinterstitially arranged in tumor site, wherein the primary radiationconductors in use are employed as a transmitter for diagnostic radiationfrom said diagnostic radiation source for diagnosis of a tumor at saidtumor site, or for therapeutic radiation from said therapeutic radiationsource for therapy of the tumor, respectively, or as a receiver forconduction of radiation from the tumor site for diagnosis of the tumor;and a distributor for distribution of radiation from the diagnostic andtherapeutic radiation source to the tumor site, and from the tumor siteto at least one diagnostic radiation sensor, wherein the distributorcomprises a plurality of primary radiation conductors arranged forconducting radiation to and from the tumor site, a plurality ofsecondary radiation conductors arranged for delivering radiation fromthe diagnostic or therapeutic radiation source or conduction ofradiation to the diagnostic radiation sensor, two flat discs abuttingagainst each other, wherein a first of said discs is fixed and thesecond of said discs is turnable relatively to the other disc, andwherein each disc has holes arranged on a circular line, wherein theproximal ends of the primary radiation conductors are fixed in the holesof the first disc and distal ends of the secondary radiation conductorsare fixed in the holes of the second disc, whereby the primary and thesecondary radiation conductors by rotation of the two discs relativeanother are connectable to each other in different constellations. 2.The system according to claim 1, wherein the circle radius of saidcircle line on one disc equals the circle radius on the other disc andwhere the holes in one disc are equally distributed on the circle linewith an angular separation of v1=(360/n1) degrees, n1 being the numberof holes, and the holes in the other disc are equally distributed on thecircle line with an angular separation of v2=(360/n2) degrees, whereinn2=m×n1, and wherein m is a multiple, which yields n2 as an integer≧1.3. A system according to claim 2, wherein n1 is the number of holes inthe fixed disc of the distributor, n1=6 and m=2, yielding n2=12 holes inthe turnable disc of the distributor.
 4. A system according to claim 1wherein every other secondary radiation conductor is part of a series ofdiagnostic radiation conductors and that a diagnostic radiationconductor in said series of diagnostic radiation conductors is arrangedfor emitting diagnostic radiation from the diagnostic radiation sourceand the other diagnostic radiation conductors in said series ofdiagnostic radiation conductors are arranged for conduction of radiationto the diagnostic radiation sensor.
 5. A system according to claim 4,wherein the diagnostic radiation source comprises a diagnostic lightsource for white, red, blue/violet or ultraviolet light.
 6. A systemaccording to claim 5, wherein a beamsplitter is associated with thediagnostic light source for blue/violet or ultraviolet light.
 7. Asystem according to claim 6, wherein the beamsplitter is a dichroicbeamsplitter, and wherein the system additionally comprises atransferring diagnostic radiation conductor arranged between thedichroic beamsplitter and the diagnostic radiation sensor.
 8. A systemaccording to claim 7, wherein the same primary radiation conductor isconfigured to record fluorescence and to transmit diagnostic radiationto the tumor site.
 9. A system according to claim 5, wherein the primaryradiation conductors distal ends are treated by a material withtemperature sensitive fluorescence emission.
 10. A system according toclaim 9, wherein the therapeutic radiation which in use is sent to thetumor site is configured to heat the tumor site, and wherein theintensity of the therapeutic radiation is controllable by a measuredtemperature in order to regulate the temperature of the tumor site atthe individual primary radiation conductors.
 11. A system according toclaim 4, wherein the radiation sensor comprises a spectrometer with atwo-dimensional detector array and the proximal ends of said otherdiagnostic radiation conductors of said series of diagnostic radiationconductors are arranged in the entrance slit of the spectrometer.
 12. Asystem according to claim 1, wherein every other secondary radiationconductor is part of a series of therapeutic radiation conductorsarranged for emission of therapeutic radiation from the therapeuticradiation source.
 13. A system according to claim 1, wherein thetherapeutic radiation source comprises a light source for coherent lightof a single fixed wavelength.
 14. A system according to claim 1, whereinthe distributor is configured for locking the turnable disc intopredetermined angular positions.
 15. A system according to claim 1,wherein the radiation conductors are optical fibers.
 16. A method forinteractive interstitial photodynamic or photothermal tumor therapy anddiagnosis, said method comprising: inserting at least two primaryradiation conductors at distal ends thereof interstitially into a tumor;activating a diagnostic radiation source and transmitting diagnosticradiation through one of said primary radiation conductors to the distalends thereof; transmitting the diagnostic radiation through tissue atsaid tumor site to distal ends of the remaining primary radiationconductors; collecting and evaluating diagnostic information fromradiation received from said tumor; automatically switching betweentumor therapy and tumor diagnostics; and controlling the tumor therapyby regulating a therapeutical radiation intensity depending on saiddiagnostic information.
 17. The method according to claim 16, furthercomprising switching between tumor diagnostics and tumor therapy byrotating a turnable disc in an optical distributor, such that differentarrangements of diagnostic and therapeutic radiation conductors areconnected to the primary radiation conductors.
 18. The method accordingto claim 17, further comprising alternatingly switching betweeninteractive interstitial photodynamic tumor therapy, photothermal tumortherapy using hyperthermia, and tumor diagnostics during the sameoccasion of treatment of said tumor site.
 19. The method according toclaim 16, wherein said inserting the at least two primary radiationconductors at the distal ends thereof interstitially into the tumorcomprises placing injection needles having a lumen in the tumor, movingthe primary radiation conductors forward through the lumen of aninjection needle to arrive outside the distal end of the needle,respectively, thereby fixing these primary radiation conductors in thetumor.
 20. The method according to claim 16, further comprising usingthe same primary radiation conductors during treatment, for integrateddiagnostics and dosimetry.